Reverse osmosis has proved to be a particularly effective separation process for efficiently and effectively providing good-tasting, potable water for drinking, cooking and the like. A variety of different apparatus have been developed for utilizing cartridges of spirally-wound reverse osmosis membranes to provide such potable water. U.S. Pat. No. 4,713,175 to Donald T. Bray is an example of such a water purifier that is designed to mount to the spout or spigot of a kitchen faucet and that delivers product water to a receptacle located on or near the sink-top. U.S. Pat. No. 4,711,723 to Donald T. Bray is an example of a water-purification apparatus which is designed to stand on the sink-top or counter-top and to operate whenever it receives water under pressure from a sink faucet or diverter or from some other supply of tap water.
Although the foregoing apparatus have proved very effective for supplying domestic households and the like with potable water, improved and more convenient apparatus are continually being sought to satisfy consumer needs and preferences.